In the late Chongzhen reign, Heyang County was flooded with corrupt officials, when the Imperial Guards suddenly descended to conduct a thorough crackdown. Spies from rival factions infiltrated the county and vied against one another, and the unspoken catchphrase among all was "All spies must die." Zhao Renbao, a minor local clerk, realizes every powerful figure intends to use him as a pawn. Determined to take control of his fate, he devises an elaborate trap within a trap of his own, outwitting corrupt nobles and officials amid the razor-thin line between life and death.